Nonparametric measures of the impact of public research expenditures on Australian broadacre agriculture

Nonparametric methods are used to measure the impact of public research expenditures on Australian broadacre agriculture over the 1953–94 period. Results using both unrestricted and 30‐year lagged specifications of the research impacts on productivity suggest that while certain aspects of the nonparametric multi‐input/output technologies are quite robust to alternative specifications (in particular, the associated Malmquist total factor productivity indexes), other aspects are less stable (in particular, the indexes on input and, to a lesser extent, output biased technical change). Internal rates of return to research expenditures on Australian broadacre agriculture are estimated to be in the 12 per cent to 20 per cent range.Crop Production/Industries, Research and Development/Tech Change/Emerging Technologies,

Beach Quality and Recreational Values: A Pictorialized Stated Preference Analysis of Residents and Tourists

Much of Hawaii’s economy relies on its unique marine environments, which are threatened by degradation from stormwater runoff. Using a stated preference method of choice-based conjoint (CBC) analysis, based on stylized photographs, this study examines both residents’ and visitors’ marginal value for levels of attributes associated with Hawaiian beach recreation. Each attribute (sand quality, water quality, congestion and water safety conditions) was significant for both residents and tourists, with water quality being the single most important attribute. There is little distinction between resident and tourist marginal value, except for a greater value lost for below average water quality among tourists.Nonmarket Valuation, WTP, Beach, Environmental Economics and Policy, Resource /Energy Economics and Policy,

Local Gromov-Witten invariants of Blowups of Fano surfaces

In this paper, using the degeneration formula we obtain a blowup formulae of local Gromov-Witten invariants of Fano surfaces. This formula makes it possible to compute the local Gromov-Witten invariants of non-toric Fano surfaces form toric Fano surface, such as del Pezzo surfaces. This formula also verifed an expectation of Chiang-Klemm-Yau-Zaslow.Comment: 13 page

Mori Dream Spaces as fine moduli of quiver representations

We construct Mori Dream Spaces as fine moduli spaces of representations of bound quivers, thereby extending results of Craw--Smith \cite{CrawSmith} beyond the toric case. Any collection of effective line bundles $\mathscr{L}=(\mathscr{O}_X, L_1,..., L_r)$ on a Mori Dream Space $X$ defines a bound quiver of sections and a map from $X$ to a toric quiver variety $|\mathscr{L}|$ called the multigraded linear series. We provide necessary and sufficient conditions for this map to be a closed immersion and, under additional assumptions on $\mathscr{L}$, the image realises $X$ as the fine moduli space of $\vartheta$-stable representations of the bound quiver. As an application, we show how to reconstruct del Pezzo surfaces from a full, strongly exceptional collection of line bundles.Comment: 25 pages, 2 figures; v2 section 3 simplified, typos corrected; v3 final versio

IMAGINE-ing interprofessional education: program evaluation of a novel inner city health educational experience

Background: Poverty is a key determinant of health that leads to poor health outcomes. Although most healthcare providers will work with patients experiencing poverty, surveys among healthcare students have reported a curriculum gap in this area. This study aims to introduce and evaluate a novel, student-run interprofessional inner city health educational program that combines both practical and didactic educational components.Methods: Students participating in the program answered pre- and post-program surveys. Wilcoxon signed-rank tests and descriptive thematic analysis were used for quantitative and qualitative data, respectively.Results: A total of 28 out of 35 participants responded (response rate: 80%). Student knowledge about issues facing underserved populations and resources for underserved populations significantly increased after program participation. Student comfort working with underserved populations also significantly increased after program participation. Valued program elements included workshops, shadowing, and a focus on marginalized populations.Conclusion: Interprofessional inner city health educational programs are beneficial for students to learn about poverty intervention and resources, and may represent a strategy to address a gap in the healthcare professional curriculum

Changes in food cravings and eating behavior after a dietary carbohydrate restriction intervention trial

Compared to low-fat diets, low-carbohydrate (CHO) diets cause weight loss (WL) over a faster time frame; however, it is unknown how changes in food cravings and eating behavior contribute to this more rapid WL in the early phases of dieting. We hypothesized that reductions in food cravings and improved eating behaviors would be evident even after a relatively short (4-week) duration of CHO-restriction, and that these changes would be associated with WL. Adult participants

Values for Recreational Beach Quality in Oahu, Hawaii

Pristine coastal environments are the key to Hawaii’s worldwide fame and attraction to tourists, yet their economic value remains understudied. This article examines preferences for characteristics associated with beach recreation in Oahu, Hawaii, among residents and tourists. Consideration is given to sand quality, water quality, congestion levels, and swimming safety conditions in the context of a choice experiment. The choice experiment conveys attribute levels almost entirely through pictures, and results suggest that this novel portrayal is well understood by respondents. Excessive congestion and water quality are regarded as the most important beach attributes, specifically the avoidance of poor water quality in favor of a chance to experience excellent water quality. Some evidence suggests that significantly different willingness to pay (WTP) exists among residents and tourists on Oahu with poor water quality and excellent water quality being more important to tourists, while residents place greater value on avoiding excessive congestion

Instabilities of Hexagonal Patterns with Broken Chiral Symmetry

Three coupled Ginzburg-Landau equations for hexagonal patterns with broken chiral symmetry are investigated. They are relevant for the dynamics close to onset of rotating non-Boussinesq or surface-tension-driven convection. Steady and oscillatory, long- and short-wave instabilities of the hexagons are found. For the long-wave behavior coupled phase equations are derived. Numerical simulations of the Ginzburg-Landau equations indicate bistability between spatio-temporally chaotic patterns and stable steady hexagons. The chaotic state can, however, not be described properly with the Ginzburg-Landau equations.Comment: 11 pages, 7 figures, submitted to Physica

The basic properties of the electronic structure of the oxygen-evolving complex of photosystem II are not perturbed by Ca 2+ removal

Ca2+ is an integral component of the Mn4O5Ca cluster of the oxygen-evolving complex in photosystem II (PS II). Its removal leads to the loss of the water oxidizing functionality. The S2′ state of the Ca2+-depleted cluster from spinach is examined by X- and Q-band EPR and 55Mn electron nuclear double resonance (ENDOR) spectroscopy. Spectral simulations demonstrate that upon Ca2+ removal, its electronic structure remains essentially unaltered, i.e. that of a manganese tetramer. No redistribution of the manganese valence states and only minor perturbation of the exchange interactions between the manganese ions were found. Interestingly, the S2′ state in spinach PS II is very similar to the native S2 state of Thermosynechococcus elongatus in terms of spin state energies and insensitivity to methanol addition. These results assign the Ca2+ a functional as opposed to a structural role in water splitting catalysis, such as (i) being essential for efficient proton-coupled electron transfer between YZ and the manganese cluster and/or (ii) providing an initial binding site for substrate water. Additionally, a novel 55Mn2+ signal, detected by Q-band pulse EPR and ENDOR, was observed in Ca2+-depleted PS II. Mn2+ titration, monitored by 55Mn ENDOR, revealed a specific Mn2+ binding site with a submicromolar KD. Ca2+ titration of Mn2+-loaded, Ca2+-depleted PS II demonstrated that the site is reversibly made accessible to Mn2+ by Ca2+ depletion and reconstitution. Mn2+ is proposed to bind at one of the extrinsic subunits. This process is possibly relevant for the formation of the Mn4O5Ca cluster during photoassembly and/or D1 repair

Stochastic Renormalization Group in Percolation: I. Fluctuations and Crossover

A generalization of the Renormalization Group, which describes order-parameter fluctuations in finite systems, is developed in the specific context of percolation. This ``Stochastic Renormalization Group'' (SRG) expresses statistical self-similarity through a non-stationary branching process. The SRG provides a theoretical basis for analytical or numerical approximations, both at and away from criticality, whenever the correlation length is much larger than the lattice spacing (regardless of the system size). For example, the SRG predicts order-parameter distributions and finite-size scaling functions for the complete crossover between phases. For percolation, the simplest SRG describes structural quantities conditional on spanning, such as the total cluster mass or the minimum chemical distance between two boundaries. In these cases, the Central Limit Theorem (for independent random variables) holds at the stable, off-critical fixed points, while a ``Fractal Central Limit Theorem'' (describing long-range correlations) holds at the unstable, critical fixed point. This first part of a series of articles explains these basic concepts and a general theory of crossover. Subsequent parts will focus on limit theorems and comparisons of small-cell SRG approximations with simulation results.Comment: 33 pages, 6 figures, to appear in Physica A; v2: some typos corrected and Eqs. (26)-(27) cast in a simpler (but equivalent) for